Advantages of spiral welded pipe
Spiral welded pipe (ssaw): It is made by rlling low-carbon carbon structural steel or low aloy structural steel strip into a tube blank according to a certain helical angle (called forming angle), and then welding the pipe seam. It can be made with narrower strip steel produces large diameter steel pipes. Its specifications are expressed by outer diameter * wall thickness. The welded pipe should ensure that the hydraulic test, the tensile strength of the weld and the cold bending performance must meet the regulations.
Advantages of spiral welded pipe:
(1) Steel pipes of different diameters can be produced by using strip steel of the same width, especially stel pipes of large diameter can be produced by narrow strip steel.
(2) Under the same pressure conditions, the stress of the spiral welded seam is smaller than that of the straight seam, which is 75% to 90% of the straight seam welded pipe, so it can withstand greater pressure. Compared with straight seam welded pipes with the same outer diameter, the wall thickness can be reduced by 10% to 25% under the same pressure.
(3) Dimensions, the general diameter tolerance does not exceed 0.12%，the deflection is less than 1/2000, and the ellipticity is less than 1%. Generally, the sizing and straightening processes can be omitted.
(4) It can be produced continuously. In theory, it can produce infinitely long steel pipes. The loss of cutting head and tail is small, and the metal utilization rate can be increased by 6% to 8%.
(5) Compared with the longitudinal welded pipe, it is flexible in operation and convenient in changing varieties and adjustments.
(6) The equipment is light in weight and low in initial investment. It can be made into a trailer- type mobile unit to produce welded pipes directly on the construction site where the pipelines are laid.
(7) It is easy to realize mechanization and automation.
Advantages of spiral welded pipe:
(1) Steel pipes of different diameters can be produced by using strip steel of the same width, especially stel pipes of large diameter can be produced by narrow strip steel.
(2) Under the same pressure conditions, the stress of the spiral welded seam is smaller than that of the straight seam, which is 75% to 90% of the straight seam welded pipe, so it can withstand greater pressure. Compared with straight seam welded pipes with the same outer diameter, the wall thickness can be reduced by 10% to 25% under the same pressure.
(3) Dimensions, the general diameter tolerance does not exceed 0.12%，the deflection is less than 1/2000, and the ellipticity is less than 1%. Generally, the sizing and straightening processes can be omitted.
(4) It can be produced continuously. In theory, it can produce infinitely long steel pipes. The loss of cutting head and tail is small, and the metal utilization rate can be increased by 6% to 8%.
(5) Compared with the longitudinal welded pipe, it is flexible in operation and convenient in changing varieties and adjustments.
(6) The equipment is light in weight and low in initial investment. It can be made into a trailer- type mobile unit to produce welded pipes directly on the construction site where the pipelines are laid.
(7) It is easy to realize mechanization and automation.
